This invention generally pertains to heterocyclic carbon compounds having drug and bio-affecting properties and to their preparation and use. In particular, the invention is concerned with various heterocyclic derivatives characterized by Formulas I and II, infra., which are inhibitors of blood platelet aggregation.
U.S. patents relating to the heterocyclic carboxylic acid and ester derivatives disclosed herein are as follows:
Pyridazine compounds in Field of Search 514/247 and 544/239.
King, et al. U.S. Pat. No. 2,712,542 discloses 2-(3-pyridazonyl)-acids having analgesic, anticonvulsant, antispasmodic and sedative activities of formula (1). ##STR2##
Baetz, U.S. Pat. No. 3,622,576 discloses diphenylpyridazones of formula (2) having psychotropic and analgesic properties. ##STR3##
Houlihan, U.S. Pat. No. 4,162,317 discloses succinic acid esters of 4,5-dihydro-3-(2H)-pyridizones having muscle relaxant activity of formula (3). ##STR4##